Here's why:
* Datum is singular.
* Data is the plural form.
* To form the possessive of a plural noun that doesn't end in 's', we add an apostrophe and an 's'.
Therefore, the correct plural possessive is data's.
Here's why:
* Datum is singular.
* Data is the plural form.
* To form the possessive of a plural noun that doesn't end in 's', we add an apostrophe and an 's'.
Therefore, the correct plural possessive is data's.